1. Technical Field
The embodiments herein generally relate to spinal stabilization devices, and more particularly to an artificial ligament assembly used for spinal stabilization.
2. Description of the Related Art
Ligaments are bands of tough, elastic, fibrous tissue that connect bones together at joints so that the joints can move. Ligaments are found at all of the joints of the skeleton (e.g., as in knees, head and neck, thorax, elbow, wrist etc.). Moreover, ligaments act to limit the motion of bones relative to each other, thus providing stability to the joints. Bone joints are vulnerable to injury for anyone involved in strenuous activities. Ligaments are more susceptible to being torn with violent twisting forces. Due to abrupt or progressive stress, a ligament is susceptible to tearing.
When a ligament is torn, it can either be repaired or replaced. Generally, repairing heals a torn ligament poorly; hence the ligament must be replaced. Most replacements come from connective tissues in a patient's own body (e.g., a knee tendon). Rehabilitation and return to full strength can take one to two years or more. To reduce rehabilitation time and provide greater strength, artificial ligaments are used. Artificial ligaments are required because the natural ligaments heal slowly and are often damaged irreparably. Various types of artificial ligament devices have been developed.
Most of the artificial ligament devices provide required tension support which is usually greater than necessary torsion limitation. The torsional movement is excessively limited (e.g., fully rigid) or has a minimal torsional micro-motion which is based solely on the material and/or geometry of the device (e.g., plate). Generally, these artificial ligament devices do not provide compression load-bearing support as well. Compression is not limited (e.g., exceedingly flexible), and there is non-load bearing with macro-motion which is based solely on the material and/or geometry (e.g., elastic band).
Also, these artificial ligament devices generally do not have a torsion limitation, and typically do not provide a controlled torsional range of motion with the skeletal body. Also, these devices generally do not provide compression and would not benefit for the spinal stabilization due to excessive flexion and extension. Furthermore, these devices generally do not provide controlled stabilization to a patient with spinal pathologies and do not assist in the restoration of natural ligamentous support.